Highly efficient and stable Ni-based catalyst for selective conversion of biomass-derived aldehydes and ketones to primary amines

Abstract

Here We report a yolk-shell structured Zr-assisted Ni-based catalyst, which could catalyze the reductive amination of a variety of biomass-derived aldehydes and ketones with high activity and robust stability. The novel LDH-derived Zr assisted-NiAl catalyst exhibits superior stability (>200 h) than traditional supported Ni/Al2O3 catalyst (<75 h) due to strong interaction between Ni0 yolk and NiAl2O4 shell. Outstanding yield of fufurylamine at 99 % is achieved under mild conditions at low temperature of 70 °C with 1 MPa H2. Other aldehydes and ketones are also transformed into primary amines with high yield above 90 % generally under mild conditions. Our study reveals that strong acidity favors the activation of imines, while strengthened hydrogen activation capability of catalyst promotes the dissociation of intermediate secondary amine to primary amine. The appropriate hydrogen activation capability regulated by Zr introduction into LDH-derived NiAl catalyst avoids over-hydrogenation of furyl-, hydroxyl- and imide-groups, which accounts for the high selectivity of mono-primary amine. Importantly, the dependence of mono-primary amine production on appropriate hydrogen activation capability of catalyst proved by this work provides ideas for tailored catalysts in the production of renewable primary amines from biomass.